The explosion of the Deepwater Horizon oil platform on April 20, 2010 resulted in the second largest oil spill in history. In this study, the distribution and chemical composition of hydrocarbons within a 45 km radius of the blowout was investigated. A complete set of hydrocarbon data were acquired from the National Oceanic and Atmospheric Administration (NOAA) and from BP, including data from 16 research missions collected over eight weeks. The distribution of hydrocarbons was found to be more dispersed over a wider area in subsurface waters than previously predicted or reported. Several hydrocarbon plumes were identified including a near-surface plume (0.5 to 50 m), two small mid-depth plume (240 to 290 m and 850 to 880 m), and a large deepwater plume approximately 1,050 to 1,300 m below surface. Water soluble compounds were preferentially extracted from the rising oil in deepwater, and were found at potentially toxic levels both in and outside of areas previously reported to contain the majority of hydrocarbons. Data collected from different research missions were measured for a wide variety of chemical compounds, but not every sample was analyzed for the same chemical compounds. To overcome the challenge of variability in sample data, a non-parametric method of evaluating the percentage of detectable results, was used for all data analysis in addition to evaluation of total sample concentrations. The two analysis techniques yielded similar results. This approach may be useful in other studies in which samples are measured for varying number of compounds and have varying detection limits. The distribution and toxicity of hydrocarbons in sediments between August and October, 2010 was also investigated and was found to be fairly localized.